The present invention relates to reclosable plastic bags and, in particular to a method of manufacturing such packages on form, fill and seal equipment.
Reclosable bags have become increasingly popular both for storage purposes and as primary packaging for foodstuffs and other commodities. The closures for such packaging consist of a pair of profiles having mating interlocking elements and may have webs to facilitate joining the zipper to the package material. A slider may be provided to facilitate opening and closing the zipper.
In U.S. Pat. No. 4,909,017 there is disclosed a method for forming reclosable bags on a form, fill and seal machine wherein the zipper runs transverse to the running direction of the bag making film. While the method disclosed in this reference and improvements that have since been made work fine for slider-less zippers, the method does not readily lend itself to applications where the zipper is provided with a slider to facilitate opening and closing because of difficulties in providing access to the slider in the finished bag.
In view of the above, it is the principal object of the present invention to provide an improved method for forming reclosable bags having slider operated zippers.
Another object is to provide such a method which provides for a package in which the zipper is readily visible and accessible to a consumer.
A further object is to provide such a method that employs conventional bag making equipment.
The above and other objects and advantages are attained in accordance with the present invention by providing a method of making reclosable packaging wherein a longitudinally extending web of film material is provided with cutouts therein. A length of zipper strip having an attached slider is applied transversely across the web of film material with the slider positioned in the cut out. The web is folded longitudinally with the zipper attached to the web and the slider positioned in the cut out and the edges of the web are longitudinally seamed to form a tube. The opposite ends of the tube are sealed to form the package. The zipper length is substantially half the width of the web.